The present invention relates to a horizontally opposed-die type edging press used for forging of a slab, i.e., for decreasing the width of a slab at a position upstream of a rolling line or downstream of a continuous casting line.
Conventional horizontally opposed-die type edging presses for forging a slab from a continuously moving billet through a strike of dies are for instance disclosed in Japanese Patent 1st Publication No. 68646/1987, Japanese Utility Model 1st Publication No. 15901/1987 and Japanese Patent 1st Publication No. 273229/1986. One of such presses will be described with reference to the above-mentioned Japanese Patent 1st Publication No. 68646/1987. In order to set the width of a slab to be forged, provided is a width setting device of the type in which a lead screw is threaded into a connecting rod fitted over an eccentric portion of a crankshaft such that the lead screw can be reciprocated in the direction of width of a slab; the lead screw is rotated through a worm in unison with a worm wheel; and the lead screw is detachably fitted at its one end into a slide upon which a die is detachably mounted, whereby distance between the opposing dies is set. Upon rotation of the lead screws, the slides are displaced to move the opposing dies toward or away from each other, thereby setting the width of a slab to be forged.
The edging press of the type described above has the following various problems:
(1) Since the width setting device is disposed in the connecting rod, load exerted to the connecting rod becomes excessive heavy so that a device for driving the edging press becomes large in size and acceleration energy for the press is increased.
(2) Since any motion of the eccentric portion of the crankshaft is transmitted to the slide through the connecting rod upon which the width setting device is disposed, the connecting rod receives impact load in forging of a slab and tends to vary in length, resulting in variation of load torque exerted to the crankshaft.
(3) Since the width setting device complicated in structure is disposed in the connecting rod which translates the rotation of the eccentric portion of the crankshaft into the reciprocal motion of the slide, inspection and maintenance of the width setting device become cumbersome so that the rate of operation of the edging press is lowered and consequently the shutdown time of the production line as a whole is increased. As a result, production efficiency cannot be improved.
The present invention was made to solve the above and other problems encountered in the conventional edging presses and has for its object to provide a horizontally opposed-die type edging press with a width setting device capable of operating at a high degree of efficiency and allowing easy inspection and maintenance.
To the above and other ends, a horizontally opposed-die type edging press in accordance with the present invention comprises slides each having a die, said slides being disposed to sandwich a slab transportation line, bearing boxes disposed on a side of the corresponding slide remote from said line, a crankshaft supported by said bearing boxes, a connecting rod for connecting an eccentric portion of said crankshaft with the corresponding slide, a parallel displacement mechanism for moving each of said slides in the direction in parallel with said line and a width setting device disposed on a side of said bearing boxes remote from said line adapted to causing the bearing boxes to displace in a direction of width of a slab to be forged.
The axis of the crankshaft may be in parallel with or perpendicular to the slab transportation line. Means for connecting the crankshaft with a drive may be flexible joints and gear boxes.
In forging a slab by the edging press with the above described construction, the width setting devices cause the bearing boxes to displace in the direction of width of a slab so as to set the width of the slab. Thereafter the crankshafts are rotated to cause the slides to reciprocate in the direction of width of the slab while the parallel displacement mechanisms cause the slides to reciprocate in the direction in parallel with the slab transportation line.
As a result, the dies are caused not only to reciprocate in the direction of width of the slab but also to move in parallel with the slab transportation line, whereby a slab is forged.
According to the present invention, the width setting device for setting a width of a slab to be forged is disposed at one side of the bearing boxes remote from the slab transportation line so that the slabs can be forged with no variation of the load torque which may otherwise be caused by the impact forces from the dies and the slides.